Weights

US Basis Weight – measures the weight of 500 sheets of paper size in its uncut form. I.e., An uncut sheet of Bond paper is 17 x 22 inches, while an uncut sheet of Cover paper is 20 x 26 inches. If 500 sheets of Bond paper (17 x 22 inches) weigh 20 lbs, then a ream of paper cut to Letter size will be labeled as 20 lb. And if 500 sheets of Cover paper (20 x 26 inches) weigh 65 lbs, then a ream of this paper trimmed to tabloid size would be marked as 65lb.